Drilling cutter

Abstract

The drilling cutter is applied to the field of machining and comprises a cutter handle, a cutter body is arranged at one end of the cutter handle, a drill tip is arranged at the end, away from the cutter handle, of the cutter body, a main cutting edge, an end edge and a chisel edge are arranged on the drill tip, and a G-shaped chip containing groove is formed in the drill tip. The drilling tool has the technical effects that in the machining process of the drilling tool, the drill tip plays a key centering role, the positive rake angle is formed at the drill tip through the design of the G-shaped chip containing groove, and as the linear speed at the absolute center of the drill tip is zero, when the drill tip is just in contact with a part, extrusion caused by machining has great damage to a drill core of the drill tip; the positive rake angle can play a cutting role when the main cutting edge drills, independent chip breaking is completed in the G-shaped chip containing groove, meanwhile, the sharpness of the chisel edge is enhanced, drill core abrasion of the drill tip is relieved, the service life of a cutter is prolonged, and the drilling efficiency and the production quality are improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of machining, in particular to a drilling tool. BACKGROUND

[0002] The drilling tool is a special tool for drilling, and is widely used in drilling operations of various materials, including steel, non-ferrous metal, plastic and the like.

[0003] In the related art, the quenching and tempering steel drilling tool is used in machining, the use of a large number of hydraulic tool shanks promotes the increase of the linear speed in machining, most of the drill tips on the market adopt a straight line shape formed by standard grinding wheel grooving, and the chips generated by the main cutting edge cannot be curled and broken through the chip pocket of the drill tip, and must rely on the cylindrical hole wall shape after the drill tip is machined to bend the chips, finally leading to the bending and breaking of the chips. Thus, there is a problem that the chips are forced to bend when encountering the cylindrical hole wall, and an opposite force is generated in the bending process, which pushes the drill tip in the opposite direction. In the machining process, the drill tip is constantly subjected to the opposite force, so the drill tip is constantly bent and retreated in the hole, resulting in the actual dynamic jumping of the drill tip.

[0004] The actual dynamic jumping of the drill tip in the above drilling tool in use causes the instability of the drill tip centering, and in combination with the increase of the linear speed in machining, the wear of the drill core of the tool is aggravated, the service life of the tool is short, and the drilling efficiency and production quality are low. SUMMARY

[0005] In order to help solve the problem of the instability of the drill tip centering in the related art, in combination with the increase of the linear speed in machining, the wear of the drill core of the tool is aggravated, the service life of the tool is short, and the drilling efficiency and production quality are low, the application provides a drilling tool, which adopts the following technical scheme: a tool shank is provided, one end of the tool shank is provided with a tool body, one end of the tool body away from the tool shank is provided with a drill tip, the drill tip is provided with a main cutting edge, an end edge and a horizontal edge, and a G-shaped chip pocket is formed in the drill tip.

[0006] In one specific implementation scheme, two chip removal grooves are formed in the tool body along the outer peripheral wall, and the two chip removal grooves extend to the tool shank in a spiral manner along the central axis of the tool body.

[0007] In one specific implementation scheme, four support edge bands are provided on the drill tip, and the four support edge bands are respectively arranged in a central symmetry along the center of the drill tip.

[0008] In one specific implementation scheme, a light trimming edge is provided on the support edge band.

[0009] In one specific implementation scheme, a peripheral edge gap is provided between the tool shank and the drill tip.

[0010] In one specific implementation, the main cutting edge is provided with a chip breaker.

[0011] In one specific implementation, the drill tip is provided with a tooth gap angle.

[0012] In one specific implementation, the drill tip is provided with an eccentric arc scraping relief angle, and the eccentric arc scraping relief angle is 8-10°.

[0013] In one specific implementation, the inclined wall of the drill tip is provided with an internal cooling hole penetrating the shank and the handle.

[0014] In one specific implementation, the drill tip is provided with a composite nano coating.

[0015] In summary, the present application has the following beneficial technical effects: in the drilling process, the drill tip plays a key centering role, the positive rake angle is formed at the drill tip through the design of the G-type chip flute, the linear speed at the absolute center of the drill tip is zero, the extrusion caused by machining greatly damages the drill core of the drill tip when the drill tip first contacts the part, the positive rake angle can play a cutting role when the main cutting edge drills, and independent chip breaking is completed inside the G-type chip flute, the sharpness of the cross edge is enhanced, the drill core wear of the drill tip is relieved, the service life of the tool is prolonged, and the drilling efficiency and production quality are improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a schematic diagram of the overall structure of the embodiment of the present application.

[0017] Figure 2 is a schematic diagram of the structure for embodying the main cutting edge in the embodiment of the present application.

[0018] Figure 3 is a schematic diagram of the structure for embodying the G-type chip flute in the embodiment of the present application.

[0019] Figure 4 is a schematic diagram of the structure for embodying the eccentric arc scraping relief angle in the embodiment of the present application.

[0020] Reference signs: 1, handle; 2, chip flute; 3, end edge; 4, finishing edge; 5, tooth gap angle; 6, cross edge; 7, peripheral edge gap; 8, main cutting edge; 9, circular arc transition chip breaker; 10, eccentric arc scraping relief angle; 11, edge band; 12, cooling hole; 13, G-type chip flute. DETAILED DESCRIPTION

[0021] The following will be described in detail in combination with the accompanying drawings. Figures 1-4 The present application will be further described in detail.

[0022] The embodiment of the present application discloses a drilling tool.

[0023] Referring to Figure 1 , Figure 2 and Figure 3 , the embodiments of the present application analyze the processing characteristics of P-type quenched and tempered materials, and the P-type quenched and tempered steel refers to medium carbon steel with a carbon content of 0.3-0.6%. Such quenched and tempered steel has good plasticity and toughness while maintaining high strength. The drill bit includes a shank 1, one end of the shank 1 is fixedly connected with a bit body, the bit body is provided with a drill tip at an end away from the shank 1, the drill tip is provided with a main cutting edge 8, an end edge 3 and a cross edge 6, the main cutting edge 8 is provided with a chip breaker, the chip breaker in the embodiments of the present application can break long strip-shaped chips into short chips, reducing the possibility of chip winding on the drill tip. The drill tip is provided with a clearance angle 5, the size of the clearance angle 5 affects the cutting force in the cutting process, and the cutting process can be optimized by reasonably designing and adjusting the clearance angle 5.

[0024] Referring to Figure 1 , Figure 2 and Figure 3 , the drill tip adopts a composite nano coating, and in the embodiments of the present application, a TiN and TiAlN multilayer coating is adopted. TiN (titanium nitride) and TiAlN (titanium aluminum nitride) are two common PVD (physical vapor deposition) coating materials, which are convenient for inhibiting the red heat of the drill bit during drilling, isolating cutting heat, and thus improving the edge durability.

[0025] Referring to Figure 1 , Figure 2 and Figure 3 , two G-type chip pockets 13 are provided on the drill tip, which provide unobstructed geometric space for chip removal of the drill tip by optimizing the chip pocket topography, and the G-type chip pockets 13 improve the chip breaking performance. At present, the drill tip realizes cutting by the size of the cutting angle and the interaction between the machined hole wall and the drill tip itself. In order to combine the processing characteristics of quenched and tempered materials, independent chip breaking is completed inside the G-type chip pocket 13. After the main cutting edge contacts the machined part, the internal and external speed difference reaches the maximum, and the drilling forms strong transverse curling, and the curling is caused by the shape of the groove of the drill tip. The bottom of the groove of the G-type chip pocket 13 is the top of the chip, and the upward curling radius of the cutting at this position is very small, and the cutting internal strain is large. When the strain of the cutting at this position reaches the maximum strain, the cutting produces cracks at the bottom of the chip pocket and expands, forming self-chip breaking, and thus improving the drill tip centering, reducing the chip resistance, and enhancing the strength of the cross edge 6.

[0026] Referring to Figure 1 , Figure 2 and Figure 3, two chip grooves 2 are formed in the outer peripheral wall of the shank, the two chip grooves 2 extend along the central axis of the shank from the drill tip to the shank 1 in a spiral manner, and in the embodiment of the application, the two chip grooves 2 are respectively communicated with the two G-shaped chip pockets 13. The drill tip is optimized in shape in the embodiment of the application, the rigidity of the drill tip is considered, the spline curve is used for performance research and development of the cross section of the drill tip, the bottom surface roughness of the chip groove 2 is mirror polished, the friction coefficient between the iron filings after cutting and the groove bottom is greatly reduced, and the chip removal is smoother.

[0027] With reference to Figure 1 , Figure 2 and Figure 3 , four support blade strips 11 are arranged on the drill tip, and the four support blade strips 11 are respectively arranged in a central symmetry along the center of the drill tip. In the high-speed machining process of the drill tip, the support blade strip 11 obtains force balance after decomposition in the x and y coordinate axes, that is, the force of the drill tip in the high-speed machining process is balanced, and the support blade strip 11 reduces the possibility of rubbing the hole wall at high speed after reducing the width, so that the linear speed can be continuously increased on the basis of the conventional linear speed without increasing the risk of wear of the support blade strip 11, thereby improving the efficiency and prolonging the service life of the tool.

[0028] With reference to Figure 1 , Figure 2 and Figure 3 , the support blade strip 11 is provided with a polishing edge 4. Generally, the support blade strip 11 of the drill tip is closely related to the stability of the drill tip itself in the drilling hole. Since the drill core circle of the drill tip is usually not large, the overall rigidity (bending resistance) of the drill tip is not high, and the drill tip is easily bent under the action of the combined force of the two cutting edges, so that the drilled hole is deflected. In the embodiment of the application, the position and width of the polishing edge 4 are researched for the high-precision machining requirement, and it is concluded that the polishing edge 4 is at the edge 52° of the drill tip, and the consistency of the hole diameter is optimal when machining P type quenched and tempered material.

[0029] With reference to Figure 1 , Figure 2 and Figure 3 , the inner cooling hole which penetrates the shank and the shank 1 is formed in the inclined wall of the drill tip, the number of the inner cooling hole is two in the embodiment of the application, and the two inner cooling holes are arranged in a central symmetry along the center of the drill tip. By selecting a large inner cooling hole diameter material, the cooling liquid flow per unit time is increased, and the cooling is more sufficient during cutting. The peripheral blade gap 7 is arranged between the shank 1 and the drill tip, and the peripheral blade gap 7 is 90%*D in the embodiment of the application, and D is the diameter of the shank 1.

[0030] With reference to Figure 1 , Figure 2 and Figure 4, the drill tip is provided with an eccentric arc scraping rear corner 10, the eccentric arc scraping rear corner 10 is 8-10°, the eccentric arc scraping rear corner 10 in the embodiment of the application is specifically 9°. In the prior art, the drill tip adopts a circular arc appearance, which can ensure the strength of the drill tip rear face, make the drill tip more versatile, and compared with a straight rear corner, the rear face support is stronger, if the rear corner angle is increased to increase the rear face space, the rigidity is weakened and the drill tip is prone to collapse. The application combines the characteristics of efficient machining of stainless steel, and the convex circular arc appearance of the drill tip rear corner ensures the strength while having impact resistance, can make the cooling liquid fully cool the rear face of the drill tip, and the material plastic deformation condition is also effectively controlled.

[0031] In addition, the cutting edge of the drill tip in the embodiment of the application can be chamfered, changing the previous powder mixing and polishing process, specifically adopting a customized drill bit passivation machine, diamond powder brush processing is used for passivating the cutting edge of the drill tip, so that the smoothness of the cutting edge and the rear face of the drill tip reaches the effect of within Ra0.1, can make the negative chamfer uniform and consistent, and the time of cutting edge processing is also saved from the original 30 seconds per piece to 15 seconds per piece. The general quenched and tempered steel drill tip generally has a service life of 30 meters, but the limit service life of the self-chip breaking chip flute 2 and the G-type chip flute 13 can reach 45 meters.

[0032] The implementation principle of the embodiment of the application is that: in the drilling tool machining process, the drill tip plays a key centering role, the drill core refers to the cutting part in the middle of the drill tip, a positive rake angle is formed at the drill tip through the design of the G-type chip flute 13, because the linear speed at the absolute center of the drill tip is zero, when the drill tip just contacts the part, the extrusion caused by machining damages the drill core of the drill tip greatly, the positive rake angle can play a cutting role when drilling (not at the absolute center), and independent chip breaking is completed inside the G-type chip flute 13, at the same time, the sharpness of the cross edge 6 is enhanced, the drill core wear of the drill tip is relieved, the tool service life is prolonged, the drilling efficiency and production quality are improved, when the drilling tool machining reaches the service life, the tool wear VB is less than or equal to 0.15 mm, and the hole wall roughness after drilling can be within Ra3.2.

[0033] The specific embodiment is only an explanation of the application, and is not a limitation of the application, and those skilled in the art can make modifications to the embodiment without creative contribution according to the needs after reading the specification, but as long as it is within the scope of the claims of the application, it is protected by the patent law.

Claims

1. A drill bit, characterized by: The utility model provides a drill bit, including handle (1), one end of handle (1) is equipped with sword body, the sword body is equipped with drill tip away from one end of handle (1), is equipped with main cutting edge (8), end blade (3) and horizontal blade (6) on drill tip, is equipped with G type chip flute (13) on drill tip.

2. The drill bit of claim 1, wherein: Two chip flutes (2) are arranged on the outer wall of the sword body, and the two chip flutes (2) extend spirally from the drill tip to the handle (1) along the central axis of the sword body.

3. The drill bit of claim 1, wherein: Four support blade zones (11) are arranged on the drill tip, and the four support blade zones (11) are arranged symmetrically along the center of the drill tip.

4. The drill bit of claim 3, wherein: The support blade zone (11) is provided with a light trimming blade (4).

5. The drill bit of claim 1, wherein: A peripheral blade gap (7) is arranged between the handle (1) and the drill tip.

6. The drill bit of claim 1, wherein: The main cutting edge (8) is provided with a chip breaking blade.

7. The drill bit of claim 1, wherein: The drill tip is provided with a tooth gap angle (5).

8. The drill bit of claim 1, wherein: The drill tip is provided with an eccentric arc scraping rear angle (10), and the eccentric arc scraping rear angle (10) is 8-10°.

9. The bore cutter of claim 1, wherein: An internal cooling hole is arranged on the inclined wall of the drill tip and penetrates the sword body and the handle (1).

10. The bore cutter of claim 1, wherein: The drill tip is coated with a composite nano coating.

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